commands: Add clk commands

This adds some basic commands to manupulate clocks on the command
line. Right now we have:

- clk_set_parent
- clk_set_rate
- clk_enable
- clk_disable
- clk_dump

The commands work based on the clock name, otherwise they behave like
the Linux Kernel C functions. clk_dump will dump the clocktree to the
console.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

commands/Kconfig

@@ -613,6 +613,14 @@ config CMD_USB
 	help
 	  The usb command allows to rescan for USB devices.
 
+config CMD_CLK
+	tristate
+	depends on COMMON_CLK
+	prompt "clock manipulation commands"
+	help
+	  Say yes here to get clk_set_rate, clk_set_parent and clk_dump
+	  commands to manipulate clocks on your system.
+
 menuconfig CMD_WD
 	bool
 	depends on WATCHDOG

commands/Makefile

@@ -74,4 +74,5 @@ obj-$(CONFIG_CMD_BASENAME)	+= basename.o
 obj-$(CONFIG_CMD_DIRNAME)	+= dirname.o
 obj-$(CONFIG_CMD_READLINK)	+= readlink.o
 obj-$(CONFIG_CMD_LN)		+= ln.o
+obj-$(CONFIG_CMD_CLK)		+= clk.o
 obj-$(CONFIG_CMD_TFTP)		+= tftp.o

commands/clk.c

@@ -0,0 +1,144 @@
+#include <common.h>
+#include <command.h>
+#include <getopt.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+
+static int do_clk_enable(int argc, char *argv[])
+{
+	struct clk *clk;
+
+	if (argc != 2)
+		return COMMAND_ERROR_USAGE;
+
+	clk = clk_lookup(argv[1]);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	return clk_enable(clk);
+}
+
+BAREBOX_CMD_HELP_START(clk_enable)
+BAREBOX_CMD_HELP_USAGE("clk_enable <clk>\n")
+BAREBOX_CMD_HELP_SHORT("enable <clk>\n")
+BAREBOX_CMD_HELP_END
+
+BAREBOX_CMD_START(clk_enable)
+	.cmd		= do_clk_enable,
+	.usage		= "enable a clock",
+	BAREBOX_CMD_HELP(cmd_clk_enable_help)
+BAREBOX_CMD_END
+
+static int do_clk_disable(int argc, char *argv[])
+{
+	struct clk *clk;
+
+	if (argc != 2)
+		return COMMAND_ERROR_USAGE;
+
+	clk = clk_lookup(argv[1]);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	clk_disable(clk);
+
+	return 0;
+}
+
+BAREBOX_CMD_HELP_START(clk_disable)
+BAREBOX_CMD_HELP_USAGE("clk_disable <clk>\n")
+BAREBOX_CMD_HELP_SHORT("disable <clk>\n")
+BAREBOX_CMD_HELP_END
+
+BAREBOX_CMD_START(clk_disable)
+	.cmd		= do_clk_disable,
+	.usage		= "disable a clock",
+	BAREBOX_CMD_HELP(cmd_clk_disable_help)
+BAREBOX_CMD_END
+
+static int do_clk_set_rate(int argc, char *argv[])
+{
+	struct clk *clk;
+	unsigned long rate;
+
+	if (argc != 3)
+		return COMMAND_ERROR_USAGE;
+
+	clk = clk_lookup(argv[1]);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	rate = simple_strtoul(argv[2], NULL, 0);
+
+	return clk_set_rate(clk, rate);
+}
+
+BAREBOX_CMD_HELP_START(clk_set_rate)
+BAREBOX_CMD_HELP_USAGE("clk_set_rate <clk> <rate_hz>\n")
+BAREBOX_CMD_HELP_SHORT("Set clock <clk> to <rate>\n")
+BAREBOX_CMD_HELP_END
+
+BAREBOX_CMD_START(clk_set_rate)
+	.cmd		= do_clk_set_rate,
+	.usage		= "set a clocks rate",
+	BAREBOX_CMD_HELP(cmd_clk_set_rate_help)
+BAREBOX_CMD_END
+
+static int do_clk_dump(int argc, char *argv[])
+{
+	int opt, verbose = 0;
+
+	while ((opt = getopt(argc, argv, "v")) > 0) {
+		switch(opt) {
+		case 'v':
+			verbose = 1;
+			break;
+		default:
+			return -EINVAL;
+
+		}
+	}
+
+	clk_dump(verbose);
+
+	return 0;
+}
+
+BAREBOX_CMD_HELP_START(clk_dump)
+BAREBOX_CMD_HELP_USAGE("clk_dump [-v]\n")
+BAREBOX_CMD_HELP_OPT  ("-v",  "verbose\n")
+BAREBOX_CMD_HELP_END
+
+BAREBOX_CMD_START(clk_dump)
+	.cmd		= do_clk_dump,
+	.usage		= "show information about registered clocks",
+	BAREBOX_CMD_HELP(cmd_clk_dump_help)
+BAREBOX_CMD_END
+
+static int do_clk_set_parent(int argc, char *argv[])
+{
+	struct clk *clk, *parent;
+
+	if (argc != 3)
+		return COMMAND_ERROR_USAGE;
+
+	clk = clk_lookup(argv[1]);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+	parent = clk_lookup(argv[2]);
+	if (IS_ERR(parent))
+		return PTR_ERR(parent);
+
+	return clk_set_parent(clk, parent);
+}
+
+BAREBOX_CMD_HELP_START(clk_set_parent)
+BAREBOX_CMD_HELP_USAGE("clk_set_parent <clk> <parent>\n")
+BAREBOX_CMD_HELP_SHORT("Set parent of <clk> to <parent>\n")
+BAREBOX_CMD_HELP_END
+
+BAREBOX_CMD_START(clk_set_parent)
+	.cmd		= do_clk_set_parent,
+	.usage		= "set a parent of a clock",
+	BAREBOX_CMD_HELP(cmd_clk_set_parent_help)
+BAREBOX_CMD_END